Toy building block



FIG. 1 is a perspective view of a design for toy building block showing my new design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a front elevational view thereof, the rear elevational view being substantially a mirror image of the front elevational view;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a left side elevational view thereof; and,

FIG. 7 is a perspective view thereof, the broken line showing of the toy building blocks is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for toy building block, as shown and described. 